The present invention relates to fluid quick connect couplers and, more particularly, to hydraulic and pneumatic quick couplers that include features of universal couplers integrated together with features of safety couplers, in a novel universal safety coupler apparatus.
Conventional pneumatic quick coupling designs typically consist of two connecting members, including a plug member or xe2x80x9cmalexe2x80x9d half and a socket member or xe2x80x9cfemalexe2x80x9d half. Usually, the socket member is connected to a source of pressurized fluid such as compressed air or the like. The plug member is selectively received into and locked with the socket member to complete a fluid circuit. Historically, the plugs have evolved into several xe2x80x9cstandardxe2x80x9d configurations or profiles. Accordingly, many varieties of quick couplers have been designed, each being adapted for limited use with a different specific male plug configuration.
Several multiple interchange or xe2x80x9cuniversalxe2x80x9d couplers have been developed to accept various male plug profiles into a single specialized socket by the use of stationary and/or sliding seals or O-rings disposed in the socket. The seals or O-rings are configured to permit sealing two or more distinctly different types or styles of male plugs into a single common universal coupler. Such universal couplers are correspondingly more complex relative to couplers which are compatible with only a single male plug type.
For safety reasons and for other considerations, several types of non-universal couplers have been developed which, by means of secondary valving, allow for safe coupling and uncoupling between the respective members. These systems provide for the controlled discharge or exhaust of entrapped air to relieve applied fluid pressure between the coupler components. This style of coupler often incorporates a means of preventing accidental disconnect under pressure. Basic to this concept is the avoidance of xe2x80x9chose whipxe2x80x9d. These safety features have been accomplished in existing designs by means of one or more cylindrical sleeve arrangements incorporating various sleeve locking and interlocking devices often accomplished with ball bearings. Other air exhausting safety couplers use push-button camming arrangements to permit disconnection only after a controlled venting period. It is believed that incorporation of such safety features is mandated by law in many European countries and has become widely accepted domestically.
There remains an unfulfilled need, however, for an improved coupler which combines the features of universality, i.e. compatibility of a single female socket with various male plug types, together with effective safety features in a simple, practical, and integrated package. The present invention contemplates such a universal safety coupler improvement which overcomes the aforementioned limitations and others.
According to one aspect of the invention, a coupling system for selectively connecting an associated fluid inlet with an associated fluid outlet is disclosed. An essentially hollow plug having a shape corresponding to one of a plurality of plug types is in fluid communication with the associated fluid outlet. A coupler is in fluid communication with the associated fluid inlet. The coupler includes a receiving region adapted for selective connection with a plug having a shape corresponding to one of the plurality of plug types. The coupler also has a lock that selectively locks the plug into the receiving region. The coupler additionally has a valve that is movable between an open position defining an operative connection between the fluid inlet and the fluid outlet whereby fluid can pass from the inlet to the outlet, and a closed position defining an operative disconnection of the fluid inlet from the fluid outlet.
Preferably, the open position of the valve further includes an operative locked condition of the lock.
Preferably, the unlocked condition of the lock is conditional upon the closed position of the valve.
Preferably, the lock includes a plurality of holes, a plurality of locking balls disposed in the holes, a locking groove disposed on the plug, and a locking sleeve that in the locked position presses the locking balls into the locking groove. The open position of the valve advantageously includes a locked position of the locking sleeve. The lock preferably further includes a sleeve spring that biases the locking sleeve into the locked position, whereby the lock engages automatically in response to insertion of the plug into the receiving region.
Preferably, plug includes a plug nose, and the receiving region includes a valve, a valve seal that deforms to seal against the plug nose, and a valve spring that biases the valve seal and the valve against the plug nose whereby a predetermined range of plug nose lengths are accommodated.
Preferably, the closed position of the valve further includes an operative vent path that vents the receiving region.
According to another aspect of the invention, a coupler for detachably coupling with an associated plug to form a fluid flow coupling is disclosed. The coupler includes an inlet region. A receiving region is adapted for detachable receipt of the associated plug, said associated plug corresponding to one of a plurality of plug types each plug type having a type of plug nose and a type of locking groove. The receiving region also preferably has a plurality of openings, with a plurality of locking members arranged in the openings of the receiving region. The coupler also has a valve having an engaged position wherein the valve operatively connects the inlet region with the receiving region whereby a fluid path therebetween is defined, and a disengaged position wherein the inlet region is operatively disconnected whereby flow therefrom is blocked and wherein the receiving region is operatively vented. The coupler additionally has a lock having a locked position wherein the lock presses the locking members into the locking groove of the associated plug whereby the associated plug is locked into the receiving region, and an unlocked position conditional upon the valve being in the closed position wherein the locking members are unlocked from the locking groove of the associated plug.
The lock preferably also has a lock spring that biases the lock into the locked position whereby the lock automatically moves into the locked position responsive to insertion of the associated plug into the receiving region.
The receiving region preferably further includes an essentially rigid valve, a deformable valve seal that conforms to the plug nose whereby the plurality of plug nose types are accommodated, and a valve spring that compresses the valve and the valve seal against the plug nose whereby the plurality of plug nose lengths are accommodated.
The coupler preferably includes a plug interlock member that cooperates with the lock and the valve whereby the lock is prevented from moving into the unlocked position when the valve is in the engaged position.
The valve preferably includes an essentially cylindrical valve sleeve, a vent, an inlet valve conduit that operatively connects the inlet with the valve sleeve, and an outlet valve conduit that operatively connects the receiving region with the valve sleeve conditional upon the valve being in the engaged position, and that operatively connects the receiving region with the vent conditional upon the valve being in the disengaged position whereby the receiving region is vented.
The lock preferably includes an essentially cylindrical locking sleeve that in the locked position surrounds the locking members whereby the locking members are pressed into the locking groove of the associated plug.
According to yet another aspect of the invention, a coupler that couples a pressurized inlet to an associated plug is disclosed. A receiving region is adapted to receive the plug, said plug corresponding to one of a plurality of plug types each having a locking groove. A lock cooperates with the locking groove to selectively lock the plug into the receiving region. A valve has an open position wherein fluid flows from the pressurized inlet to the receiving region and a closed position wherein the pressurized inlet is isolated from the receiving region.
Preferably, a valve interlock maintains the valve in its closed position responsive to an unlocked condition of the lock. Advantageously, a latch interlock maintains the lock in an unlocked condition responsive to removal of a plug from the receiving region, said second interlock disengaging responsive to insertion of a plug into the receiving region whereby the inserted plug is selectively lockable.
Preferably, a plug interlock maintains the lock in its locked position responsive to an open condition of the valve.
Preferably, a vent path selectively vents the receiving region in response to a closing of the valve. The vent path is advantageously disposed in an area away from an associated user""s hand whereby the vent path dispels the vented fluid away from the user""s hand.
Preferably, the lock is an automatic lock that locks the plug into the receiving region responsive to insertion of the plug into said receiving region. The automatic lock optionally includes a spring biasing of the locking mechanism toward its locked position.
Preferably, the receiving region includes a spring biased valve that adapts to the plug length whereby the receiving region adapts to the lengths of the plurality of plug types.
Preferably, the receiving region includes a pliant valve seal that essentially conforms to the shape of the plug nose whereby the receiving region adapts to the shapes of the plurality of plug types.
The plurality of plug types preferably include at least two of: an industrial interchange type plug type, a Tru-Flate plug type, and an ARO plug type.
According to still yet another aspect of the invention, a universal safety coupler for coupling an associated plug to a fluid inlet includes a receiving area adapted to receive a plurality of plug types, a lock that cooperates with a groove of the associated plug to selectively lock the plug into the receiving area, a valve that selectively opens to enable fluid flow from the fluid inlet to the receiving area, a latch interlock that prevents the lock from locking without having a plug inserted into the receiving area, a valve interlock that prevents the valve from opening when the lock is unlocked, and a plug interlock that prevents the lock from unlocking when the valve is open.
A vent path is also preferably provided, that is operatively connected to the valve wherein closing the valve opens the vent path whereby the receiving region is vented.
One advantage of the present invention is that it is compatible with several types of male plugs.
Another advantage of the present invention is that it provides safety features including flow cutoff and downstream pressure exhaust in a universal-type coupler.
Yet another advantage of the present invention is that it provides quick-connect capability for multiple plug types without sacrificing safety features.
Still yet another advantage of the present invention is that it provides a pressure-side safety socket which is compatible with a plurality of male plug types.
Still further advantages and benefits of the present invention will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiment.